| D.U.S.T Management Ltd | Wholesale & retail | 2019 |
| D.W. Renovations Ltd | Construction | 2026 |
| D2 Jewels Ltd | Wholesale & retail | 2024 |
| D2DISPLAY Ltd | Manufacturing | 2026 |
| D3 Consultancy Limited | Information & communication | 2018 |
| D3 Solutions Limited | Professional & scientific | 2008 |
| D4D DESIGNERS4DESIGNERS Ltd | Administrative & support | 2008 |
| D4J UK Limited | Administrative & support | 2022 |
| D5 Design Limited | Professional & scientific | 2013 |
| D5XR Limited | Professional & scientific | 2024 |
| D7782549BA Limited | Information & communication | 2012 |
| D8ATRANSMISSION Limited | Information & communication | 2012 |
| DA Bisons Inc Limited | Information & communication | 2026 |
| DA Bizz Welding Limited | Administrative & support | 2015 |
| DA Detail Consultants Limited | Professional & scientific | 2025 |
| DA Harris Ltd | Wholesale & retail | 2020 |
| DA Silver Limited | Real estate | 2023 |
| DA Vinci MK Limited | Wholesale & retail | 2026 |
| Daad Real Estate Limited | Extraterritorial | 2016 |
| Daad Technologies Limited | Information & communication | 2019 |
| Daag Ventures Ltd | Real estate | 2026 |
| Daas Tech Ltd. | Information & communication | 2017 |
| Daazni Ltd | Wholesale & retail | 2025 |
| DAB Property Services Ltd | Professional & scientific | 2020 |
| Dabhand Touring Limited | Information & communication | 2025 |
| Daco Developers Ltd | Construction | 2020 |
| Daco Technology Holdings Limited | Information & communication | 2013 |
| Daco Technology Limited | Information & communication | 2007 |
| Dactree Limited | Construction | 2023 |
| Dadababa Properties Ltd | Real estate | 2024 |
| Daddication Community CIC | Education | 2025 |
| Daddy ASH Limited | Wholesale & retail | 2022 |
| Daffex Ltd | Information & communication | 2024 |
| Daffodil Care Limited | Health & social care | 2021 |
| Daffodil Commercial Properties Limited | Real estate | 2025 |
| Daifuku Automotive U.K. Ltd | Manufacturing | 1968 |
| Daikoku Imports Limited | Wholesale & retail | 2023 |
| Dailund Group Limited | Administrative & support | 2016 |
| Daily Dwayne Limited | Administrative & support | 2015 |
| Daily Nationwide Distribution Limited | Transport & logistics | 1987 |
| Daily Smile Limited | Professional & scientific | 2012 |
| Daily Wake UP Ltd | Professional & scientific | 2015 |
| Daimler Truck Financial Services UK Limited | Financial services | 2021 |
| Daimler Truck UK Limited | Wholesale & retail | 2016 |
| Dairo Healthcare Ltd | Administrative & support | 2022 |
| Daisol Limited | Financial services | 2016 |
| Daisy & Spa Ltd | Other services | 2025 |
| Daisy Family Homes Ltd | Health & social care | 2024 |
| Daisy Holdings Ltd | Administrative & support | 2026 |
| Daisy Lane Gift Boxes Limited | Wholesale & retail | 2022 |
| Daisyway Limited | Information & communication | 2013 |
| Dajys Limited | Manufacturing | 2016 |
| Dakine Limited | Extraterritorial | 2025 |
| Dakkrit Ltd | Information & communication | 2023 |
| Daks Consultancy Limited | Professional & scientific | 2014 |
| Dakshata Properties Ltd | Real estate | 2022 |
| Dakshi Convenience Store Ltd | Wholesale & retail | 2023 |
| DAL Signal Limited | Construction | 2023 |
| DAL UK Properties Ltd | Real estate | 2025 |
| Dal's Tutoring Service Ltd | Education | 2026 |
| Dalaxy Ventures Limited | Real estate | 2025 |
| Dale Advisory Group Limited | Professional & scientific | 2025 |
| Daley Enterprises Limited | Professional & scientific | 2025 |
| Dalkeith Consultancy Limited | Professional & scientific | 2013 |
| Dallas Burston Estates Limited | Agriculture & fishing | 1983 |
| Dallyn & Co Limited | Professional & scientific | 2025 |
| Dalscote Little LLP | | 2015 |
| DAM Consulting Ltd | Professional & scientific | 2024 |
| Damach Machinery Limited | Manufacturing | 2024 |
| Damayanti Ltd | Health & social care | 2026 |
| Damian Prins Consulting Ltd | Administrative & support | 2025 |
| Damien Massias Ltd | Education | 2014 |
| Damien Varon Ltd | Other services | 2021 |
| Damn Good Creative Ltd | Arts & recreation | 2011 |
| Damn Good Exhibitions Ltd | Arts & recreation | 2011 |
| Damn Good Limited | Manufacturing | 2004 |
| Damngoodcars Ltd | Wholesale & retail | 2014 |
| DAN Dexter Ltd | Administrative & support | 2022 |
| DAN Health Care Solutions Ltd | Health & social care | 2011 |
| DAN JUN Digital Technology Ltd | Wholesale & retail | 2025 |
| DAN Services Ltd | Wholesale & retail | 2025 |
| Dan&Sons Refurbish Ltd | Construction | 2025 |
| Dan's Bathroom Maintenance Ltd | Administrative & support | 2017 |
| Danamar Records Limited | Wholesale & retail | 2024 |
| Danben Capital Limited | Financial services | 2026 |
| Dancebox Milton Keynes LLP | | 2015 |
| Dancebox Studios & Theatre Works Ltd | Education | 2023 |
| Dancecode Ltd | Education | 2022 |
| Dandara Central Limited | Construction | 2025 |
| Dandara Northern Home Counties Limited | Construction | 2020 |
| Dandara UK Services Limited | Administrative & support | 2021 |
| Dandbuk Limited | Information & communication | 2010 |
| Dandelion Therapy Rooms Ltd | Other services | 2026 |
| Daneon Limited | Health & social care | 2021 |
| Daniel Adams Removals Limited | Transport & logistics | 2016 |
| Daniel ALI Properties Ltd | Households | 2022 |
| Daniel Butterfield Ltd | Administrative & support | 2016 |
| Daniel Consultants Ltd | Education | 2020 |
| Daniel Goodwin and Associates Limited | Professional & scientific | 2010 |
| Daniel James Estate Agents Limited | Real estate | 2019 |